1. Technical Field
This invention relates generally to protective textile sleeves, and more particularly to multilayer textile sleeves and to their method of construction.
2. Related Art
It is known to first fabricate individual layers of textile material and then attach the individual layers to one another in a secondary operation to construct a multilayer material. For example, if the desired multilayer material being constructed requires an inner layer to provide one type of property, such as low friction, and an outer layer to provide another type of property, such as insulation and/or abrasion resistance, one piece of textile material can be constructed in a first operation; a second piece of material can be constructed in a second operation, and then, the first and second pieces of material can be joined in a third operation via material separate from the first and second pieces of material to provide the multilayer material. Although the end product is made having the desired properties, it comes at an expense, particularly given the manufacturing inefficiencies compiled over numerous operations.
Further, in order to provide the protection required to prevent unwanted exposure of an elongate member or members being carried in a cavity of a sleeve, as shown in the prior art of FIGS. 1A-1B, it is known to wrap the elongate member or members, such as wires or a fluid carrying pipe, for example, with a first sleeve 1, with the first sleeve 1 then being wrapped with a separate second sleeve 2. This is particularly useful in vehicle applications that must meet increasing demands to reduce the voltage of high voltage units to 60V or less within a five second interval after a crash condition to minimize the potential for electric arcing, commonly referred to as a short circuit, between the wires within the sleeve and electrically conducting members in the vehicle. In a crash condition, sleeves are subject to damage via extreme concentric loading, and thus, a multi-layered wall sleeve is desired to ensure the resulting damage does not leave the wires within the sleeve exposed. Although the separate, individually wrapped sleeves can ultimately provide the type of protection desired, it comes at a cost. Having to manufacture the sleeves 1, 2 separately from one another and further, having to wrap the sleeves 1, 2 separately, and in some cases fixing the sleeves 1, 2 to one another, is inefficient and costly. Further, with the sleeves 1, 2 being constructed of separate pieces of material, typically the diametric area occupied by the sleeves 1, 2 is increased, thereby occupying valuable space, which in some cases may not be readily available. Further, yet having to use separate sleeves to achieve the protection desired requires stocking and inventorying double the number of sleeves as for a single sleeve application, which adds further complexity and cost.